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SubjectRe: [PATCH v2] leds: pca963x: Fix open-drain initialization
On Mon 2019-11-18 23:02:55, Zahari Petkov wrote:
> Before commit bb29b9cccd95 ("leds: pca963x: Add bindings to invert
> polarity") Mode register 2 was initialized directly with either 0x01
> or 0x05 for open-drain or totem pole (push-pull) configuration.
>
> Afterwards, MODE2 initialization started using bitwise operations on
> top of the default MODE2 register value (0x05). Using bitwise OR for
> setting OUTDRV with 0x01 and 0x05 does not produce correct results.
> When open-drain is used, instead of setting OUTDRV to 0, the driver
> keeps it as 1:
>
> Open-drain: 0x05 | 0x01 -> 0x05 (0b101 - incorrect)
> Totem pole: 0x05 | 0x05 -> 0x05 (0b101 - correct but still wrong)
>
> Now OUTDRV setting uses correct bitwise operations for initialization:
>
> Open-drain: 0x05 & ~0x04 -> 0x01 (0b001 - correct)
> Totem pole: 0x05 | 0x04 -> 0x05 (0b101 - correct)
>
> Additional MODE2 register definitions are introduced now as well.

Thanks, applied.
Pavel

--
(english) http://www.livejournal.com/~pavelmachek
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